Blister sheet loading apparatus with bounce prevention means

ABSTRACT

Apparatus for loading medication doses ( 4′ ) into a cavity ( 15′ ) of a blister sheet ( 12′ ) made from a resilient plastics material, is provided with a number of horizontally-arranged containers one of which is shown at ( 6′ ). Each container can be operated to release a solid medication dose ( 4′ ) into a cavity ( 15′ ) of a selected blister. The blister sheet to have its cavities loaded with medication doses is supported horizontally on a table spaced beneath the level at which the containers ( 6′ ) are located. A thick horizontal plate ( 1 ) is disposed between the level of the containers and the level of the table, and an array of inclined and axially-parallel bores ( 2′ ) are formed through the plate. The upper ends of the bore associated with each blister cavity can be located beneath the container which is to deliver a dose to the cavity so that a released dose travels down the bore and impacts against one side of the bore which acts to deflect the dose and thus reduce its vertical momentum. The dose is released from the lower end of the bore and impacts against the inside upper, wall of the cavity. The risk of damage by impact of released doses with one another in the cavity is reduced and the risk of a dose bouncing back out of the cavity through impacting on its resilient floor is avoided.

FIELD OF THE INVENTION

THIS INVENTION relates to the prevention of bounce occurring when smallobjects are loaded into pockets into which they may be subsequentlysealed. The invention is particularly well-suited, although notexclusively so, to preventing solid medication doses, such as tablets,from bouncing when falling into a pocket formed by the cavity of ablister of a blister sheet.

For convenience and ease of understanding, the description of theinvention which follows has been limited to its use in loadingmedication doses into blister cavities of a blister sheet but it is tobe understood that the invention is applicable to a much wider range ofusage than this particular activity.

STATE OF THE ART

The provision of prescribed medication to a patient by means of apre-loaded blister package is commonly used to enable the patient tocarry several days supply of prescribed doses of medication. The dosesare prescribed by a doctor and appropriately packaged by a pharmacist toprovide the patient with a sealed blister sheet having individualblisters marked with the days and times at which the doses in eachblister are to be administered to the patient.

It is convenient to mechanize the loading of the blister sheet with theprescribed doses to save time and apparatus to achieve this has beendevised which relies on a large number of storage containers havingbottom openings from which tablets are released into the cavities ofblisters in accordance with a computerized program. The programdetermines which blister of the blister sheet is to be loaded at aparticular moment with a particular prescribed medication. The blistersheet is normally loaded while inverted and has its blisters extendingdownwardly into respective openings provided in a horizontal supporttable. The table can be indexed horizontally in its own plane by amechanism to bring each blister in turn to a pre-arranged loadingposition at which the appropriate medication dose selected from one ofthe containers can be released into its cavity.

The blister sheet is normally made from a plastics material which has anatural resilience, and it is convenient to rely on gravity to transfera dose from a selected storage container to the blister cavity. Howeverthe natural resilience of the blister sheet can cause a dose to bounceback out of the blister cavity if it is the first dose to be placed init, and there is also a risk that the descending dose will impact on adose already in the cavity and damage one or both doses as aconsequence.

To reduce the risk of damage occurring when a dose is dropped into ablister, the distance through which the dose drops from the underside ofthe container should be made as small as is practical. However there isa limit to the reduction of this distance if there is to be no risk of adose bouncing out of the cavity interfering with the operation of theindexing mechanism.

OBJECT OF THE INVENTION

An object of this invention is to reduces the risk of problems occurringduring loading of doses or other hard objects into a blister cavity.

THE INVENTION IN ITS BROADEST ASPECT

In accordance with the broadest aspect of the invention apparatus forloading individual cavities of a blister sheet with small hard objectsreleased into the cavities from above, includes: first means forlocating individual containers holding the objects at a level above theposition of the blister cavity to be loaded; second means for releasingan object from the container so that it follows a path leading downwardstowards the cavity; and, third means located in the path of descent ofthe object and acting to retard its rate of descent to an acceptablelevel (as below defined) before it reaches the cavity. The expression“acceptable level” referred to above, is a level at which a releasedobject will not bounce back out of the cavity nor will its impact onother objects already loaded into for different objects to be loadedinto the blister cavity.

PREFERRED FEATURES OF THE INVENTION

Preferably the third means is formed by a deflector which is struck bythe object during its descent to absorb part of its momentum and thusslow it down.

Suitably the deflector is in the form of an elongated opening such as abore, extending downwardly through a plate and at an angle to the planeof the plate, the upper end of the opening being located beneath abottom outlet of the container and the lower end of the opening beinglocated above a loading position at which the blister cavity to beloaded is positioned.

Conveniently the lower end-portion of the opening is shaped to direct anobject descending through it towards a side-wall of the blister cavity

A Narrower Aspect of the Invention

In accordance with a narrower aspect of the invention apparatus forloading cavities of a blister sheet with prescribed doses of medication,includes: a support table provided with means for positively locatingrespective blisters of the blister sheet at a level spaced beneath anddisplaced horizontally with respect to a position at which dose-storagecontainers can be located, and a deflector positioned between thestorage containers and the table to deflect a dose falling from thestorage container laterally towards a blister cavity intended to receiveit.

Preferred Features of the Narrower Aspect of the Invention

Preferably the deflectors referred to immediately above, are provided bythe internal surfaces of respective axially parallel bores formedthrough a relatively thick and horizontal plate located between thelevel of the blister sheet on the table, and the level of thedose-discharge position of the container.

The portion of the lower end-portion of the bore opposite the side firststruck by a descending tablet may be rebated to avoid the risk oftablets stacking up against one side of the cavity and possiblyinterfering with the correct operation of the apparatus.

When a particular dose is to be loaded into a selected blister cavity,an indexing mechanism of the table may be operated to bring the cavityof the blister to be loaded and its associated deflector, to a positionat which the deflector is located beneath the lower end of a storagecontainer from which the dose is to be released. The dose then strikesthe deflector during its descent, and its momentum is reduced as aconsequence. The deflection also preferably deflects the descending dosetowards a side-wall of the selected blister. Impact with the side wallslows down the descent still further so that the risk of the descendingdose damaging itself or other doses which may already be in the blisteris reduced still further.

INTRODUCTION TO THE DRAWINGS

The invention will now be described in more detail, by way of examples,with reference to accompanying partly-diagrammatic drawings, in which:

In the drawings

FIG. 1 is a perspective view from above of a relatively thick platepenetrated by an array of axially-parallel bores inclined to the planeof the plate and providing one form of deflecting means;

FIG. 2 is a diagrammatic plan view of the plate of FIG. 1;

FIG. 3 is a side view of the plate of FIG. 2;

FIG. 4 is an end view of the plate of FIG. 2;

FIG. 5 shows diagrammatically, and to a greatly enlarged scale, the pathof descent of a dose through one bore of the plate, the dose beingreleased from a dose-storage container above the plate and strikingagainst a deflecting surface provided by the interior wall of the boreso that the dose is deflected towards the upper internal wall of ablister cavity beneath; and,

FIG. 6 shows a modification of FIG. 5 and where identical parts bearidentical reference numerals but they are primed, and the lower end ofthe bore is rebated.

DESCRIPTION OF FIRST EXAMPLE OF THE INVENTION

For convenience the example of the invention now to be described isdesigned to be used in conjunction with apparatus of the general designdescribed in U.S. Pat. Nos. 7,225,597 B1; 7,426,814 B2; and, 7,510,099B2. These specifications are hereby inserted by way of reference toenable the reader to understand how the apparatus works and to avoidburdening the present specification with unnecessary detail well knownin the art. In the first two of the above-numbered prior art patentspecifications a blister support table is identified in FIG. 1 by thereference number ‘thirty’ and the same reference numeral is used in FIG.5 of the present specification to denote a like part. The support table30 of FIG. 5 is provided with openings 14 for the reception ofrespective blisters 15 of an inverted blister sheet 12 moulded from aresilient plastics material and placed blistered-side down on the table30.

FIGS. 1 to 4 show a flat thick nylon plate 1 formed with an array ofidentical cylindrical and axially-parallel bores 2 inclined at an angleto the plane of the plate of about sixty degrees. The plate 1 isslightly less than two centimeters thick. The diameter of each hole isslightly more than sixteen millimeters. None of these dimensions orangles is critical and are only given as one example of the invention.

FIG. 5 shows one of a number of dose-storage containers 6 located at alevel spaced above the plate 3 and at a dose-discharge positionvertically above the upper end of a bore 2. A mechanism (not shown) atthe lower end of the container 6 and controlled by a computerizedcontrol system (also not shown) allows a dose to be released from thecontainer 6 in response to a control signal generated by the system andcontrolling operation of the apparatus.

Operation of the First Example of the Invention

A dose in the form of a hard solid medication tablet or pill, shown at 4in FIG. 5, is dropped from the lower end of the container 6 into theupper end of the bore 2 immediately beneath, and descends along the fallline indicated by a broken line in FIG. 5. As the axis of the bore 2 isat thirty degrees to the vertical, the dose strikes against the insidewall of the bore intermediate its ends, at a location 7. The distancethrough which the dose falls before striking the location 7 is foundempirically and ensures that the momentum of the dose 4 is, insufficientto cause damage to I when impacting on the location 7. This falldistance may be varied in the apparatus to achieve this result and itwill be found empirically and changed to suit different types of dose.The contact of the dose with the location 7 acts to reduce the verticalmomentum of the dose 4 and deflects it down the inclined bore 2 towardsits lower end. The dose leaving the lower end still has a horizontalcomponent of velocity so that it impacts on the side wall of the blistercavity positioned beneath the lower end of the bore 2 and associatedwith it.

Were the dose 4 allowed to fall vertically onto the floor of the cavity,there would be a risk that the resilience of the material from which theblister sheet is made, might bounce the dose 4 back out of the cavity.It might then cause damage to an indexing mechanism used to move thetable 30. There is also risk that a dose descending vertically into theblister cavity from the bore 2 could have sufficient momentum to impactagainst, and possibly damage itself and/doses already in the blistercavity.

First Modification of Described Example

In the modification of FIG. 5 shown in FIG. 6, a rebate 100 is providedon the side of the lower portion—of the bore 2 opposite the location 7.This rebate 100 serves to accommodate overflow of doses within thecavity of a blister being loaded, and also to prevent doses fromstacking up at one side of the blister and possibly blocking the lowerend of the bore 2.

Interpretation of the Width of the Wording Used in This Specification

Although the invention has been specifically described in the aboveexamples with reference to medication doses being loaded into blistercavities, it is to be understood that its usage is not limited to thisapplication. The invention is capable of being used in any apparatuswhere it is required to reduce the velocity of descent of hard solidobjects which might otherwise free-fall with an undesirably highvelocity. The deflecting bores of such apparatus may, for example, beused to reduce the velocity with which tablets or other solid medicationdoses are inserted into respective single dose blisters, or to orientatethe dose to a desired position required for entry into a blister.

1. Apparatus for loading individual cavities of a blister sheet withsmall hard objects released into the cavities from above, including:first means for locating individual containers holding the objects at alevel above the position of a blister cavity to be loaded; second meansfor releasing an object from the container so that it follows a pathleading downwards towards the cavity; and, third means located in thepath of descent of the object and acting to retard its rate-of descentto an acceptable level before it reaches the cavity.
 2. Apparatus asclaimed in claim 1, in which the third means is formed by a deflectorwhich is struck by the object during its descent to absorb part of itsmomentum and thus slow it down
 3. Apparatus as claimed in claim 2, inwhich the deflector is in the form of a bore inclined downwardly througha horizontal plate, the upper end of the bore being located beneath abottom outlet of the container and the lower end of the bore beinglocated above a loading position for the blister cavity.
 4. Apparatus asclaimed in claim 3, in which the bore is shaped to direct an objectdescending through it towards an upper side-wall of the blister cavity.5. Apparatus for loading cavities of a blister sheet with prescribeddoses of medication, including: a support table provided with firstmeans for positively locating respective blister cavities of the blistersheet at a level spaced beneath and displaced horizontally with respectto the position at which dose-storage containers can be located, and adeflector positioned between the storage containers and the table todeflect a dose falling from the storage container laterally towards ablister cavity intended to receive it.
 6. Apparatus as claimed in claim5, in which the deflectors are provided by the internal surfaces ofrespective axially-parallel and inclined bores extending between upperand lower surfaces of a relatively thick horizontal plate disposedbetween the dose-discharge position of the containers and the positionof the blister sheet.
 7. Apparatus as claimed in claim 5, in which thelower end-portion of the bore opposite its side first struck by adescending dose, is formed with a rebate.
 8. Apparatus as claimed inclaim 5, including an indexing mechanism for traversing the deflectorsand table horizontally to bring the cavity of a selected blister to beloaded together with its associated deflector, to a position beneath thedose-discharge position of the dose-storage containers.